RUDN University Chemists Developed Cheap and Eco-Friendly Surfactants
Surfactants are common both in the industry and in our everyday life. They are used as bases for detergents, added to lubricants and construction materials (concrete mixes, cement, and drilling fluids), and protect equipment from corrosion. The most effective of them are gemini surfactants that contain two hydrophilic (water-attracting) groups. However, there also “pseudo” gemini surfactants that have one hydrophilic and one hydrophobic (water-resistant) group of atoms bound together. An international team of chemists including partners from RUDN University synthesized several new “pseudo” gemini surfactants and confirmed that their performance characteristics were on par with the existing compounds. The new synthesis method is quite cost-efficient, works at room temperature, and does not require expensive reagents.
“The creation of cheap methods for the synthesis of gemini surfactants with satisfactory performance characteristics can be a turning point for the chemistry of detergents. We focused both on the development of synthetic methods and on studying the properties of new compounds,” said Fedor Zubkov, a PhD, and an Assistant Professor at the Department of Organic Chemistry, RUDN University.
To create new compounds, the chemists used six common higher fatty acids: capric, lauric, myristic, palmitic, stearic, and oleic acid. The hydrophilic properties of the new surfactants came from amines synthesized based on two affordable reagents—hexamethylenediamine and epoxypropene. To obtain a surfactant, the team dissolved an amine and one one the acids (at the ratio 1:2) in acetone at room temperature and then concentrated the solvent. The final products looked like viscous yellow liquids. The molecules of the surfactants were formed due to electrostatic interaction between oxygen atoms in the carboxylic groups of the acids and amino groups in the amine.
Other important characteristics of surfactants are foam formation and foam stability. Five out of six new surfactants formed foam in a water solution, and in the case of two of them (based on lauric and myristic acids), the volume of produced foam exceded the volume of the initial solution 3 to 4 times. The compounds based on palmitic and stearic acids produced less foam, but it was more stable and lasted up to three days. These and other characteristics of the new compounds make them promising for the skincare industry, medicine, anti-corrosion treatment of construction and industrial facilities, and oil recovery increase.
“Gemini surfactants and their synthesis are a burning issue for modern chemistry, as they can potentially replace traditional monomeric surfactants and make the chemical industry move environmentally friendly,” added Fedor Zubkov.
The work was published in the Journal of Molecular Liquids.
RUDN mathematicians investigated the possibility of combining 5 GNR technology and WiGig — a high-frequency range that allows you to transfer data at speeds up to 10 Gbps. This will smooth traffic fluctuations in 5Gnetworks and cope with user requests.
Scientists from the Winogradsky Institute of Microbiology RAS, RUDN University, St. Petersburg State University and the Tyumen Scientific Centre SB RAS studied the microbial communities from several lakes of the Yamal Peninsula. It turned out that methanotrophs (bacteria that use methane as a source of energy) consume methane more actively in the deep mature lakes of the peninsula than in small thermokarst lakes. In this regard, methane emissions into the atmosphere from the surface of deep lakes are low, and only small (relatively younger thermokarst lakes with constitutional ground ice) can make a significant contribution to methane emissions in the north of Western Siberia. Thus, bacteria perform an important function for the climate balance — they reduce the emission of methane into the atmosphere.
RUDN University physicists have described the conditions for the most efficient operation of long mirror-based variant of cyclotron in the autoresonance mode. These data will bring better understanding of plasma processes in magnetic traps.